The aim of this project is to evaluate methods of preventing blindness, visual disability and disabling complications due to inflammatory eye diseases. The specific problems studied include: a) Therapeutic trials for trachoma in which evaluations are made of different antibiotics on severe endemic trachoma in North Africa or mild trachoma in American Indians. The results of therapy are judged in terms of clinical improvement, by the changes in ocular bacterial pathogens and by the prevalence of the trachoma agent in conjunctival smears. b) Herpes simplex virus infections of the eye: Two standard methods of treatment for herpetic epithelial ulcers are being compared in patients with this disorder. In addition, patients are being followed to observe the natural history of this often blinding disease. Animal studies are being carried out to evaluate new chemotherapeutic agents for use in the treatment of herpetic keratitis. c) Other eye inflammations: Studies are being made of the natural history of certain other inflammatory eye diseases including adenovirus conjunctivitis, inclusion conjunctivitis, allergic keratoconjunctivitis, acute hemorrhagic conjunctivitis, superficial punctate keratitis and others. d) Methodological approaches in the analysis of therapeutic trials: In carrying out the studies on trachoma and herpes simplex infection it has been necessary to develop and apply a number of clinical and statistical approaches. These include the routine use of clinical photographs of trachoma and herpes for standardization of observers and the analysis of observer variation.